Growing-up is characterized by active self-determination in the sphere of marriage and family relations. From the standpoint of the age-psychological approach in the logic of psychological age structure-the social situation of development, new formations and leading activity-the dynamics of the cognitive, valuable-and-emotional, regulative-and-behavioral, motivational and reflective components of family selfdetermination was revealed for the first time in senior teens (from 15 to 16 years old), adolescence (from 17 to 19 years old) and youth (from 20 to 22 years old). In 2012-2019 the study was attended by 1.281 students of Astrakhan State University, the Astrakhan branch of the Russian Presidential Academy of National Economy and Public Administration, a branch of Russian State University for the Humanities in Astrakhan, Astrakhan State Polytechnic College, Astrakhan College of Computer Technology. In senior teens the valuable-and-emotional component prevails. Adolescence is a determining factor in demonstrating cognitive and valuable-and-emotional components. In youth, the cognitive, valuable-andemotional, regulative-and-behavioral, motivational and reflective components are distributed more evenly than in other age-related periods. The age-psychological approach to the analysis of mental development in the ontogenesis makes it possible to consider readiness for family self-determination as a private new formation of adolescence (from 17 to 19 years old), and family self-determination as an important agerelated new formation of youth (from 20 to 22 years old).